- Sat Feb 07, 2009 9:22 am
#65595
Hi there,
I am using the HMC6352 sensor:
I use the Raw Magnetometer mode ( Output mode byte = 0x01 )
Measurement summing is disables.
From the pdf document:
Raw Magnetometer Modes: These X and Y raw magnetometer data readings are the internal sensor values measured
at the output of amplifiers A and B respectively and are 10-bit 2’s complement binary ADC counts of the analog voltages
at pins CA1 and CB1. The leading 6-bits on the MSB are zero filled or complemented for negative values. The zero count
value will be about half of the supply voltage. If measurement averaging is implemented, the most significant bits may
contain values of the summed readings.
So my assumption is that I get a 10 Bit value and the leading 6 Bit´s are one´s OR zero´s depending on the sign of the measurement.
But what I get from the sensor are values in the range +-32768 so it seems to be NOT a 10 bit value either a 15 bit value. The impressive thing is that the values are correct because when I plot the data I get exact sin / cos plots and a really nice circle for an xy plot. I double checked my code it´s ok. So is there someone out there who has used the raw mode yet ?
I am using the HMC6352 sensor:
I use the Raw Magnetometer mode ( Output mode byte = 0x01 )
Measurement summing is disables.
From the pdf document:
Raw Magnetometer Modes: These X and Y raw magnetometer data readings are the internal sensor values measured
at the output of amplifiers A and B respectively and are 10-bit 2’s complement binary ADC counts of the analog voltages
at pins CA1 and CB1. The leading 6-bits on the MSB are zero filled or complemented for negative values. The zero count
value will be about half of the supply voltage. If measurement averaging is implemented, the most significant bits may
contain values of the summed readings.
So my assumption is that I get a 10 Bit value and the leading 6 Bit´s are one´s OR zero´s depending on the sign of the measurement.
But what I get from the sensor are values in the range +-32768 so it seems to be NOT a 10 bit value either a 15 bit value. The impressive thing is that the values are correct because when I plot the data I get exact sin / cos plots and a really nice circle for an xy plot. I double checked my code it´s ok. So is there someone out there who has used the raw mode yet ?